Brother Drew, Bob Brister's link is another great point on the amount of antimony. That slipped my mind and now makes it interesting on when some of these tests were taken and when antimony first started being used. This could explain a lot.
I have read from the different shot manufacturers on what their antimony content is and most seem to be in the 4-6% content but starting at #4 shot the antimony is very little. That would make sense as it would be harder to deform than #8's.
It would be interesting to note what happens to shot in a wad once the trigger is pulled. How long it is together before separation?
